The Complete Woodworking Calculator & Cutting Optimizer
A full carpentry & woodworking toolbox in one page: a code-aware stair calculator, a compound-angle solver for crown molding and flared boxes, joinery layout calculators (dovetails, box joints, mortise & tenon), a kerf-aware sheet-goods nesting optimizer, a kerf-aware board cut-list optimizer, and board-foot / wood-movement / lumber-weight calculators — every result illustrated with a live, to-scale diagram.
Planning tool, not a substitute for your building code or a test cut. Every calculator on this page is a planning aid built on standard, widely-published carpentry formulas. Stair geometry must be checked against your local building code before you cut a single stringer; compound-angle results should always be proven on scrap first (saws vary, and material thickness changes the math slightly); cutting-list results assume straight, square material and don't account for defects, grain-matching, or wood movement. Always wear eye and hearing protection and follow your tools' manuals.
What's In This Toolbox
Everything below runs live in your browser as you type — change any number and every result, table and diagram updates instantly. No plans are uploaded anywhere, so it's just as usable offline or on a jobsite with patchy signal as it is at the bench.
Enter your total rise and target riser/tread size — get the exact number of steps, riser and tread dimensions, stringer length and angle, a comfort-rule check, and a fully dimensioned side-profile drawing.
Compound Angle Solver
One verified formula, two uses: crown-molding miter & bevel for any wall corner and spring angle, or the same math relabeled for flared box, basket and planter sides. Plus a polygon-segment solver and a roof pitch/rafter calculator.
Joinery Layout Calculators
Dovetail spacing with a to-scale pin/tail drawing, box/finger joint sizing, mortise & tenon proportioning, plus quick reference tables for dowels, biscuits and pocket-hole screws.
Sheet Cutting Optimizer
Build a parts list, set your sheet size and blade kerf, and get a nested cutting diagram per sheet — with sheets needed, offcuts, and material utilization, kerf loss included.
Board Cutting Optimizer
Same idea for linear stock — lumber, molding, extrusion, pipe. Enter your cut list and stock length, get the fewest boards needed with a labeled cut diagram for each one.
Board Feet, Wood Movement & Weight
Price out lumber in board feet, estimate how much a panel will expand or contract across seasons by species, and estimate the weight of a finished piece or a stack of stock.
Why Kerf Matters (and why most cut-list tools skip it)
Every cut removes material — a typical table saw blade takes 2.5–3.2mm (1/8"), a track saw or circular saw 1.8–2.5mm, a bandsaw as little as 0.5–1.5mm
Ignore kerf on a 20-cut sheet layout and you can be off by 2"+ of material — enough to lose an entire extra part
Both cutting optimizers below let you set your exact kerf so the plan matches your actual blade or bit
When in doubt, measure your own blade's kerf directly (cut a scrap, measure the slot) rather than trusting a spec sheet
How To Use This Guide
Each tab is independent — jump straight to whichever calculator you need. Every module has its own unit toggle (metric/imperial) where relevant, and every diagram is generated from your live inputs, not a stock illustration, so what you see always matches your numbers exactly.
New to compound angles? The Angles tab includes a plain-language walkthrough of exactly where each input is measured on the actual material, with a diagram — you don't need to already know the jargon.
Stair Calculator
Enter your total rise (floor to floor) and target step size. The calculator divides the rise into equal risers, checks the result against three standard comfort rules and common minimum/maximum guidelines, and draws the stair to scale.
Inputs
Nosing and headroom are used for the guideline checks below; they don't change the riser/tread math itself. Stringer stock width feeds the open-stringer strength check.
Side profile — to scale from your inputs
Number of risers
–
Number of treads
–
steps you walk on
Actual riser height
–
Stair angle
–
from horizontal
Total run
–
nosing to nosing
Stringer length
–
Comfort & Guideline Checks
Check
Target
Your stair
Result
These are widely-used residential guidelines (similar in spirit to US IRC-style rules), not a substitute for your local building code — spans, riser/tread limits and headroom minimums vary by jurisdiction and by stair type (main stair vs. deck vs. attic/utility).
Open Stringer Strength Check
When you notch a straight board into a zigzag stringer, the wood remaining below the deepest point of each notch (the "throat") is what carries the load. For stock width W, this remaining depth is W − tread × sin(angle), measured perpendicular to the board.
Remaining throat
–
Common guidance calls for at least 3.5″ (89mm) of remaining throat, with 5″+ preferred for open (cut) stringers — this is exactly why 2×12 stock is the standard choice for notched stringers rather than 2×10. Closed/housed stringers (treads let into a routed dado) sidestep this limit entirely.
Compound Angle Solver
Three related calculators live here: a compound miter/bevel solver (crown molding and flared box sides share the exact same geometry), a regular-polygon segment solver (picture frames, planters, cupolas), and a roof pitch/rafter calculator.
Inputs
90° = a standard square inside/outside corner. Use whatever the corner actually reads for odd angles (bay windows, hexagonal rooms, tapered boxes).
Molding lies flat on the saw table, upside-down and backwards: the edge that touches the ceiling rides against the fence, the edge that touches the wall sits up off the table. Set the miter (blade rotation) and bevel (blade tilt) to the values on the right, then always prove the cut on scrap before committing good material — every saw and every piece of crown fits slightly differently.
Plan view — corner & miter line
Cross-section — spring angle
Miter angle (saw rotation)
–
off square, both saw halves
Bevel angle (blade tilt)
–
from vertical
Flip the bevel tilt direction on alternating pieces of the same cut (left piece / right piece), and for an outside corner the piece orientation on the fence mirrors the inside-corner setup — the angle numbers themselves don't change, only which face rides where. See the plan-view diagram for this cut's specific left/right layout.
"6 rise per 12 run" is a standard 6/12 pitch — about 26.6°. Adjust the two pitch numbers or think of them as any rise:run ratio.
Roof section, to scale
Pitch
–
Common rafter length
–
Hip / valley length
–
45° equal-pitch hip
Plumb cut angle
–
from vertical
Seat (level) cut angle
–
from horizontal
Joinery Layout Calculators
Lay out four of the most common woodworking joints from your actual board dimensions, plus quick reference for dowels, biscuits and pocket-hole screws.
Inputs
Tail-board face, to scale — mark centerlines directly from this spacing
Tail angle
–
Tail width (narrow)
–
Tail width (wide face)
–
Pins between tails
–
Layout runs half-pin, tail, pin, tail, pin … tail, half-pin across the board —
Inputs
Set your dado stack (or router bit) to the actual finger width shown below — cutting each finger with that exact width bit/stack is what makes the count come out even.
Rule of thumb: tenon thickness ≈ 1/3 of stock thickness (a 3/4″ rail gets a 1/4″ tenon), centered so the shoulders are even front and back. Blind mortises are typically cut to about 2/3 of the receiving piece's thickness, leaving solid material behind.
Dowel Joint Quick Calculator
Suggested dowel Ø
–
~40% of stock thickness, nearest standard size
Dowel count
–
~6″ spacing, 2 minimum
Keep dowel holes at least 2× the dowel diameter from any edge, and use fluted/spiral-groove dowels so trapped glue and air can escape.
Biscuit Size Reference
Biscuit
Size
Minimum material thickness
#0
47 × 15mm
~1/2″ (13mm)
#10
53 × 19mm
~5/8″ (16mm)
#20
56 × 23mm
~3/4″ (19mm)
Mini
13/16 shapes
~3/8″ (10mm)
Space biscuits roughly 6–8″ apart along a joint; keep at least one biscuit's width in from every edge and corner.
Pocket-Hole Screw Reference (typical settings)
Material thickness
Typical screw length
Drill stop-collar setting
1/2″ (13mm)
1″ fine-thread
~1/2″ from tip
3/4″ (19mm)
1 1/4″ coarse-thread
~3/4″ from tip
1″ (25mm)
1 1/2″ coarse-thread
~1″ from tip
1 1/2″ (38mm)
2 1/2″ coarse-thread
~1 3/8″ from tip
Use fine-thread screws in hardwoods and MDF, coarse-thread in softwoods and plywood. Always check your jig manufacturer's exact chart — this table is a general starting point, not brand-specific data.
Sheet Cutting Optimizer
Build your parts list, set your sheet size and blade/bit kerf, and get a nested cutting layout — sheets needed, offcuts, and material utilization, kerf loss included. Uses guillotine (straight, full-length) cuts only, so every layout is directly cuttable on a table saw or track saw — the engine tries several packing strategies per run and keeps whichever uses the fewest sheets. Very tight layouts may still be improvable by hand or dedicated nesting software.
Sheet & Blade Settings
Typical kerf: table saw ~1/8″ (3mm), track/circular saw ~3/32″ (2.3mm), CNC/router bit — use the bit diameter.
Results
Sheets needed
–
Utilization
–
Waste
–
Material cost
–
Parts List
LabelWidth (in)Height (in)Qty
Cutting Diagrams
part offcut / waste
Board / Linear Cutting Optimizer
The 1D version of the sheet optimizer — for lumber, molding, extrusion, edge banding or pipe. Enter your cut list and stock length, and get a best-fit-decreasing layout: the fewest boards needed, with a labeled diagram for each one.
Stock & Blade Settings
All cut pieces are assumed to come from the same stock length. If you're mixing lengths from the lumberyard, run this once per stock length.
Results
Boards needed
–
Utilization
–
Total waste
–
Material cost
–
Cut List
LabelLength (in)Qty
Cutting Diagrams
part offcut
Board Feet, Wood Movement & Lumber Weight
Price lumber the way yards actually sell it, plan for how much a panel will move across the seasons, and estimate the weight of a finished piece or a stack of stock.
Board Feet Calculator
Board feet (per piece)
–
Total board feet
–
Total cost
–
1 board foot = 144 cubic inches (a 1″×12″×12″ piece). Yards price rough lumber this way regardless of the actual width/length you buy.
Wood Movement Estimator
Expected movement
–
New width
–
Movement figures are approximate, averaged reference values (species varies board to board) — for panels, drawer bottoms and tabletops, always build in an expansion gap and use a construction method (breadboard ends, buttons, slotted screw holes) that lets wood move freely across its width.
Lumber & Panel Weight Estimator
Estimated weight
–
Approximate air-dry densities (~12% MC). Actual weight varies with moisture content, so treat this as a shipping/handling planning estimate, not a scale reading.
Build Out Your Woodshop
A practical shopping list organized the way you'd actually build a shop up — core power tools first, then the precision layout gear that makes every calculator above actually usable at the bench, then joinery jigs, then consumables and finishing.
Core Power Tools
Table Saw
The anchor tool for ripping sheet goods and boards square and straight.
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